Wireless communication systems deliver a wide variety of communication services to mobile users via wireless connections to the telecommunications infrastructure. These wireless systems employ radio techniques to allow mobile user devices to access various base stations in a wireless communication network, often in a cellular geometry. The base stations, in turn, are connected to mobile switching centers which route connections to and from the mobile user devices to other users on different communications networks, such as the public switched telephony network (PSTN), Internet, and the like. In this manner, users that are away from fixed sites or are on the move may receive various communication services such as voice telephony, paging, messaging, email, data transfers, video, Web browsing, and the like.
In one aspect, various radio frequencies are employed for the wireless interconnections between the base station and mobile users, and in order to maintain communications between wireless users sharing the scarce radio spectrum allocated for wireless communication services a common set of protocols are used. One such important protocol relates to the access method used to connect a mobile user device or access terminal to the wireless communications network. Various access methods include frequency division multiple access (FDMA), time division multiple access (TDMA), code division multiple access (CDMA), and orthogonal frequency division multiplex (OFDM). OFDM utilizes a plurality of carriers spaced apart in the frequency domain such that data modulated on each carrier is orthogonal to the others.